1. Field of the Invention
The present invention relates to an absorption refrigerating machine (including an absorption type hot/cold water service machine).
2. Description of the Related Art
The absorption refrigerating machine of this type includes, for example, a known absorption refrigerating machine 100X (see Patent Document 1) as shown in FIG. 3. In this absorption refrigerating machine 100X, high temperature and high-pressure vapor is supplied to a heat exchanger pipe 1A provided within a high temperature regenerator 1 via a heat source fluid supply pipe 10. A diluted absorbent solution within the high temperature regenerator 1 is heated and boiled through a pipe wall of the heat exchanger pipe 1A to thereby radiate heat. High temperature drain, which has been condensed by the heat radiation and has been discharged from the heat exchanger pipe 1A to an exhaust heat fluid pipe 10A, is supplied to a heat recovery device 8 which is provided in an absorbent solution pipe 13 for connecting the high temperature regenerator 1 and an absorber 5, along with an absorbent solution pump 14, a low temperature heat exchanger 6, and a high temperature heat exchanger 7. The high temperature drain heats a diluted absorbent solution delivered through the absorbent solution pipe 13 from the absorber 5 to the high temperature regenerator 1 by the absorbent solution pump 14. As a result, the required heat capacity of the heat source fluid inputted through the heat source fluid supply pipe 10 is reduced.
Further, as shown in FIG. 4, another absorption refrigerating machine 100Y having the same purpose as the machine 100X, is also known (see Patent Document 1). In this pump 14. As a result, the required heat capacity of the heat source fluid inputted through the heat source fluid supply pipe 10 is reduced.
Further, as shown in FIG. 4, another absorption refrigerating machine 100Y having the same purpose as the machine 100X, is also known (see Patent Document 1). In this absorption refrigerating machine 10Y, a part of an absorbent solution pipe 13 downstream from a low temperature heat exchanger 6 is branched into an absorbent solution pipe 13A and an absorbent solution pipe 13B. One absorbent solution pipe 13A is provided with a high temperature heat exchanger 7. The other absorbent solution pipe 13B is provided with a heat recovery device 8. As shown in FIG. 5, another absorption refrigerating machine 100Z is also known (see Patent Document 1). In this absorption refrigerating machine 100Z, a heat recovery device 8 and a heat recovery device 9 are positioned in series on an exhaust heat fluid pipe 10A. In the heat recovery device 8, a diluted absorbent solution is discharged from a high temperature heat exchanger 7 and flows into a high temperature regenerator 1. In the heat recovery device 9, a diluted absorbent solution is discharged from a low temperature heat exchanger 6 and flows into a high temperature heat exchanger 7. The diluted absorbent solutions are heated by high temperature drain, which is flowing through an exhaust heat fluid pipe 10A.
Further, in any of the above absorption refrigerating machines, a concentrated absorbent solution supplied through an absorbent solution pipe 12 from a low temperature regenerator 2 to the absorber 5 heats, in a low temperature heat exchanger 6, a diluted absorbent solution supplied from the absorber 5 to the high temperature regenerator 1 through the absorbent solution pipe 13. As a result, the required heat capacity of the heat source fluid supplied through the heat source fluid supply pipe 10 is reduced.
[Patent Document 1]
Japanese Unexamined Patent Application Publication No. 2001-56160 (FIGS. 1, 12 and 15)
However, in the aforementioned conventional absorption refrigerating machine, when the heat exchange efficiency of the low temperature heat exchanger is raised, the temperature of the cooling water supplied to the absorber falls suddenly. Thereby, when the temperature of the diluted absorbent solution discharged from the absorber falls suddenly, the temperature of the concentrated absorbent solution exchanging heat with the diluted absorbent solution in the low temperature heat exchanger and supplied from the low temperature regenerator to the absorber decreases considerably, and the concentrated absorbent solution crystallizes, which result in a situation where the operation becomes impossible.